Area Forecast Discussion
Issued by NWS Sterling, VA

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844
FXUS61 KLWX 090204
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
904 PM EST Mon Dec 8 2025

.SYNOPSIS...
Canadian high pressure will move into the area tonight and Tuesday.
A quick moving clipper system will pass through the Great Lakes
Wednesday. A secondary cold front follows suit on Thursday. Yet
another fast moving frontal system may reach the area Friday.

&&

.NEAR TERM /THROUGH TONIGHT/...
Current observations across the region show continued light snow
showers down along the I-64 corridor. These are finally starting
to taper off in the past hour, and that trend will continue into
this evening. High pressure over the Great Lakes will gradually
build overhead, and continue ushering in very cold and dry air.
Clouds may hang around until the second half of the night. Even
without maximized radiational cooling, the cold advection and
very low dew points will still allow most areas to drop into the
teens. The urban cores and bayshore will stay "warmer" in the
low 20s. Some of the colder valleys could drop into the single
digits, especially where there is snow pack. Any residual
moisture or slush will likely freeze on untreated surfaces.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
The surface high will slide off to the south and east Tuesday.
Despite return flow by afternoon, cold air will remain in place,
with most areas staying in the 30s during the day. Dry weather is
expected, although a shortwave trough aloft will increase mid and
high level clouds.

The pressure gradient will tighten Tuesday night as a clipper-type
low moves into the Great Lakes. This could bring gusts into the 30
to 40 mph range on the ridges, and keep a light southerly wind in
place in the lower elevations. Clouds will also continue to
thicken. However, it may not be enough to stop the temperatures
from dropping back into the 20s. Some precipitation may
approach from the west but most likely holds off until after
sunrise. Most of the warm advection precipitation will remain
along and west of the Allegheny front, although some models
bring some light precipitation across northern parts of the
area. There is a small chance this could be a wintry mix if it
starts early enough. Otherwise it would just be rain as
temperatures rise into the 40s with gusty south-southwest winds.
Even in the Alleghenies, temperatures will likely rise above
freezing in most spots, which may result in some rain mixing at
times, and any snow accumulations limited to the higher ridges.

The low will move into the St. Lawrence Valley Wednesday evening as
the mid and upper trough axis dives toward the region. Upslope
moisture will change fully to snow in the Alleghenies. There
remains some spread on how much moisture will be available, but at
least several inches of snow is probable. Winds will also increase,
potentially to near Wind Advisory caliber on the highest peaks.
Therefore some near-blizzard conditions can`t be ruled out. Wind
chill values will also drop into the 0 to 10 degree range in this
area. Winds won`t be quite as gusty in the lower elevations, and
little precipitation will spill east of the Alleghenies. Temperatures
will drop back into the mid 20s to mid 30s.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
The long term period will start off on Thursday with troughing along
the East Coast, ridging along the West Coast, and west-northwesterly
flow across much of the CONUS between those two features. A strong
area of low pressure is expected to track toward the Canadian
Maritimes on Thursday, with strong cold advection ensuing in its
wake over the Northeast/Mid-Atlantic. A few snow showers may linger
to the west of the Allegheny Front, but dry conditions are expected
further east. It will be a chilly day, with high temperatures in the
30s and lower 40s for most (20s mountains). Winds may gust to around
20-30 mph out of the northwest, making it feel even colder.

West-northwesterly flow will continue aloft across much of the CONUS
to end the week. Guidance suggests that multiple clipper-like
systems may track toward the area out of Canada. Forecast spread
remains large with these systems, but at least the Alleghenies
should experience chances for snow. Further east, mainly dry
conditions are expected, but some snow could also be possible Friday
into Friday night depending on how those systems track. Guidance
favors well below normal temperatures, with highs likely struggling
to get out of the 30s this coming weekend.

&&

.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
Significant improvement seen in the past hour at CHO, but some
light snow flurries continue for now, resulting in slight VSBY
reductions. Low-end VFR to MVFR CIGs are expected at CHO through
the first half of the night.

As strong high pressure builds in, winds turn light overnight,
with VFR conditions expected everywhere else.

VFR conditions continue for Tuesday and Wednesday. As high
pressure moves off the coast, winds shift to southerly on
Tuesday, picking up in intensity during the late afternoon to
evening period with gusts to around 15 to 20 knots. Further
upticks in wind are expected for Wednesday ahead of a fast
moving clipper-like system. Gusts up to 20 to 30 knots are
possible before winds shift to westerly late Wednesday behind
the associated cold front.

VFR conditions are expected on both Thursday and Friday. Winds will
be gusty out of the northwest on Thursday, and then lighter out of
the west on Friday.

&&

.MARINE...
Small Craft Advisories are in place through tonight for the
southern waters due to residual gusty winds.

High pressure will slide across the area Tuesday, providing
lighter winds that will quickly become southerly. The gradient
increases by Tuesday evening as this high exits the coast. Small
Craft Advisories will likely be required for Tuesday night,
especially along the bay. Strong southerly winds continue
Wednesday in response to a quick-moving low pressure system in
the Great Lakes. Gusts up to 25 to 30 knots are possible this
period. The associated cold front will cross Wednesday night,
while advisory conditions will remain likely.

Small Craft Advisories appear likely on Thursday within
northwesterly flow. A few Gale gusts can`t be ruled out during that
time. Sub-SCA level westerly winds are expected on Friday but
will increase Friday night.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 2 AM EST Tuesday for ANZ532-533-
     540>542.
     Small Craft Advisory until 6 AM EST Tuesday for ANZ534-537-543.

&&

$$

SYNOPSIS...ADS
NEAR TERM...ADS/CJL
SHORT TERM...ADS
LONG TERM...KJP
AVIATION...ADS/CJL/KJP
MARINE...ADS/CJL/KJP